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A123898
Expansion of e.g.f.: exp(2*(exp(exp(x/(1-x)) -1) -1)/(2 - exp(exp(x/(1-x) ) -1 ))).
1
1, 2, 16, 186, 2822, 52656, 1163546, 29664158, 856061120, 27560034858, 978535914122, 37963915297028, 1597135176454118, 72393848302855722, 3516235184103738928, 182148333985907278130, 10022182002655953791542, 583611259991958617165592, 35852747516653556289308282
OFFSET
0,2
LINKS
MAPLE
seq(coeff(series(exp(2*(exp(exp(x/(1-x))-1)-1)/(2-exp(exp(x/(1-x))-1))), x, n+1)*n!, x, n), n = 0 .. 20); # G. C. Greubel, Aug 06 2019
MATHEMATICA
With[{m=20}, CoefficientList[Series[Exp[2*(Exp[Exp[x/(1-x)]-1]-1)/(2-Exp[Exp[x/(1-x)]-1])], {x, 0, m}], x]*Range[0, m]!] (* G. C. Greubel, Aug 06 2019 *)
PROG
(PARI) my(x='x+O('x^20)); Vec(serlaplace( exp(2*(exp(exp(x/(1-x))-1)-1)/(2-exp(exp(x/(1-x))-1))) )) \\ G. C. Greubel, Aug 06 2019
(Magma) m:=20; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( Exp(2*(Exp(Exp(x/(1-x))-1)-1)/(2-Exp(Exp(x/(1-x))-1))) )); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Aug 06 2019
(Sage) m = 20; T = taylor(exp(2*(exp(exp(x/(1-x))-1)-1)/(2-exp(exp(x/(1-x))-1))), x, 0, m); [factorial(n)*T.coefficient(x, n) for n in (0..m)] # G. C. Greubel, Aug 06 2019
CROSSREFS
Sequence in context: A052606 A011553 A291816 * A118644 A183205 A006335
KEYWORD
nonn
AUTHOR
Karol A. Penson, Oct 18 2006
EXTENSIONS
Terms a(17) onward added by G. C. Greubel, Aug 06 2019
STATUS
approved